what type of interface are you using to record. if you are routing your tracks through a mixer( external) that you have your instrument plugged into, all the sounds from that mixer will be recorded on your track. check the path of your backing tracks to make sure they are not routed to a channel on your mixer. a good way to do this is use headphones either on your computer out(headphone out) or on the mixer. if you use the computer to monitor your recording( speakers) do not plug any mics in the mixer or turn them off. they will pick sound from the speakers. headphones instead of speakers is better. either from the computer or the mixer. if you use a mixer for monitoring and recording, run the output from the computer to the mixer( 1/8 stereo out to RCA in on mixer) you can switch the tape input on and off on the mixer so that the backing tracks from the computer are not in the main mix on your mixer. don't plug the computer into a channel. only into (tape in or CD in). hope this helps.